The present invention relates to a substance delivery device comprising a paperboard strip, which includes at least one of substance toxic to insects or a perfume. The present invention also relates to a method for manufacturing such a device. More particularly, but not exclusively, the present invention relates to a mosquito coil comprising a paperboard coil impregnated with a substance toxic to mosquitoes and a method of manufacturing the same.
U.S. Pat. No. 5,447,713 discloses a mosquito coil manufactured from wood fibres and/or wood chips and a binder. The mixture of ingredients is pressed to form a board from which the coils are punched. The wood fibres or chips remain discrete and separate and are held together by the binder. The use of a binder to give the coil mechanical stability means that the coil tends to be brittle. A significant proportion of coils manufactured from such resin-bound boards are damaged either during distribution or by subsequent handling by the consumer.